The known methods for locating a moving magnetic object comprise determining the position or the orientation of the magnetic object from measurements of an array of tri-axial magnetometers, this array comprising N tri-axial magnetometers mechanically linked to one another with no degree of freedom to retain a known distance between each of these magnetometers, where N is an integer number greater than 5.
A tri-axial magnetometer is a magnetometer suitable for measuring the projection of the magnetic field on three non-colinear measurement axes. Such a magnetometer measures the direction of the magnetic field. Furthermore, generally, this magnetometer also measures the amplitude or the norm of the magnetic field.
For example, such a method is disclosed in the patent application CN10 136 1660A. The use of an array of magnetometers makes it possible to very accurately locate the magnetic object.
However, the simultaneous use of a large number of magnetometers implies that there are a large number of measurements to be processed simultaneously, which requires a significant computation power to locate the moving object. Furthermore, the use of an array of magnetometers implies significant consumption since each magnetometer of this array is powered simultaneously.
Prior art is also known from:    US2002/171427A1,    U.S. Pat. No. 6,263,230B1,    US2007/167703A1,    U.S. Pat. No. 6,675,123B1,    Richard J KOZICK et Al: “Algorithm for tracking with an array of magnetic sensors”, Sensor array and multichannel signal processing workshop, 2008, SAM 2008, 5th IEEE, Piscataway, N.J., USA, 21 Jul. 2008, pages 423-427;    U.S. Pat. No. 6,269,324B1.